Extract history introspection from "versions" command

3 files changed, 98 insertions, 105 deletions

diff --git a/Library/Homebrew/cmd/bottle.rb b/Library/Homebrew/cmd/bottle.rb
index e9e39d49c..6d3f9ba92 100644
--- a/Library/Homebrew/cmd/bottle.rb
+++ b/Library/Homebrew/cmd/bottle.rb
@@ -2,7 +2,7 @@ require 'formula'
 require 'bottles'
 require 'tab'
 require 'keg'
-require 'cmd/versions'
+require 'formula_versions'
 require 'utils/inreplace'
 require 'erb'
 require 'extend/pathname'
@@ -123,7 +123,9 @@ module Homebrew extend self
     if ARGV.include? '--no-revision'
       bottle_revision = 0
     else
-      max = f.bottle_version_map('origin/master')[f.pkg_version].max
+      ohai "Determining #{f.name} bottle revision..."
+      versions = FormulaVersions.new(f)
+      max = versions.bottle_version_map("origin/master")[f.pkg_version].max
       bottle_revision = max ? max + 1 : 0
     end
 
diff --git a/Library/Homebrew/cmd/versions.rb b/Library/Homebrew/cmd/versions.rb
index af59ccb3a..302c7c3bc 100644
--- a/Library/Homebrew/cmd/versions.rb
+++ b/Library/Homebrew/cmd/versions.rb
@@ -1,10 +1,10 @@
-require 'formula'
+require "formula"
+require "formula_versions"
 
 module Homebrew extend self
   def versions
     raise "Please `brew install git` first" unless which "git"
-    raise "Please `brew update' first" unless (HOMEBREW_REPOSITORY/".git").directory?
-
+    raise "Please `brew update` first" unless (HOMEBREW_REPOSITORY/".git").directory?
     raise FormulaUnspecifiedError if ARGV.named.empty?
 
     opoo <<-EOS.undent
@@ -13,107 +13,12 @@ module Homebrew extend self
         https://github.com/Homebrew/homebrew-versions
     EOS
     ARGV.formulae.all? do |f|
-      relative_path = f.pretty_relative_path
-      f.versions do |version, sha|
-        print Tty.white.to_s
-        print "#{version.to_s.ljust(8)} "
-        print Tty.reset.to_s
-        puts "git checkout #{sha} #{relative_path}"
+      versions = FormulaVersions.new(f)
+      path = versions.repository_path
+      versions.each do |version, rev|
+        print "#{Tty.white}#{version.to_s.ljust(8)}#{Tty.reset} "
+        puts "git checkout #{rev} #{path}"
       end
     end
   end
 end
-
-
-class Formula
-  def versions
-    versions = []
-    rev_list do |sha|
-      version = version_for_sha sha
-      unless versions.include? version or version.nil?
-        yield version, sha if block_given?
-        versions << version
-      end
-    end
-    return versions
-  end
-
-  def bottle_version_map branch='HEAD'
-    map = Hash.new { |h, k| h[k] = [] }
-    rev_list(branch) do |rev|
-      formula_for_sha(rev) do |f|
-        bottle = f.stable.bottle_specification
-        unless bottle.checksums.empty?
-          map[f.pkg_version] << bottle.revision
-        end
-      end
-    end
-    map
-  end
-
-  def pretty_relative_path
-    if Pathname.pwd == repository
-      entry_name
-    else
-      path
-    end
-  end
-
-  private
-    def repository
-      @repository ||= begin
-        if path.to_s =~ HOMEBREW_TAP_DIR_REGEX
-          HOMEBREW_REPOSITORY/"Library/Taps/#$1/#$2"
-        else
-          HOMEBREW_REPOSITORY
-        end
-      end
-    end
-
-    def entry_name
-      @entry_name ||= path.relative_path_from(repository).to_s
-    end
-
-    def rev_list branch='HEAD'
-      repository.cd do
-        IO.popen("git rev-list --abbrev-commit --remove-empty #{branch} -- #{entry_name}") do |io|
-          yield io.readline.chomp until io.eof?
-        end
-      end
-    end
-
-    def text_from_sha sha
-      repository.cd do
-        `git cat-file blob #{sha}:#{entry_name}`
-      end
-    end
-
-    IGNORED_EXCEPTIONS = [SyntaxError, TypeError, NameError,
-                          ArgumentError, FormulaSpecificationError,
-                          FormulaValidationError,]
-
-    def version_for_sha sha
-      formula_for_sha(sha) {|f| f.version }
-    end
-
-    def formula_for_sha sha, &block
-      mktemp do
-        path = Pathname.pwd.join("#{name}.rb")
-        path.write text_from_sha(sha)
-
-        # Unload the class so Formula#version returns the correct value
-        begin
-          old_const = Formulary.unload_formula name
-          nostdout { yield Formula.factory(path.to_s) }
-        rescue *IGNORED_EXCEPTIONS => e
-          # We rescue these so that we can skip bad versions and
-          # continue walking the history
-          ohai "#{e} in #{name} at revision #{sha}", e.backtrace if ARGV.debug?
-        rescue FormulaUnavailableError
-          # Suppress this error
-        ensure
-          Formulary.restore_formula name, old_const
-        end
-      end
-    end
-end
diff --git a/Library/Homebrew/formula_versions.rb b/Library/Homebrew/formula_versions.rb
new file mode 100644
index 000000000..d4bad4584
--- /dev/null
+++ b/Library/Homebrew/formula_versions.rb
@@ -0,0 +1,86 @@
+class FormulaVersions
+  IGNORED_EXCEPTIONS = [
+    ArgumentError, NameError, SyntaxError, TypeError,
+    FormulaSpecificationError, FormulaValidationError,
+  ]
+
+  attr_reader :f
+
+  def initialize(f)
+    @f = f
+  end
+
+  def repository
+    @repository ||= if f.path.to_s =~ HOMEBREW_TAP_DIR_REGEX
+      HOMEBREW_REPOSITORY/"Library/Taps/#$1/#$2"
+    else
+      HOMEBREW_REPOSITORY
+    end
+  end
+
+  def entry_name
+    @entry_name ||= f.path.relative_path_from(repository).to_s
+  end
+
+  def each
+    versions = Set.new
+    rev_list do |rev|
+      version = version_at_revision(rev)
+      next if version.nil?
+      yield version, rev if versions.add?(version)
+    end
+  end
+
+  def repository_path
+    Pathname.pwd == repository ? entry_name : f.path
+  end
+
+  def rev_list(branch="HEAD")
+    repository.cd do
+      IO.popen("git rev-list --abbrev-commit --remove-empty #{branch} -- #{entry_name}") do |io|
+        yield io.readline.chomp until io.eof?
+      end
+    end
+  end
+
+  def file_contents_at_revision(rev)
+    repository.cd { `git cat-file blob #{rev}:#{entry_name}` }
+  end
+
+  def version_at_revision(rev)
+    formula_at_revision(rev) { |f| f.version }
+  end
+
+  def formula_at_revision rev, &block
+    f.mktemp do
+      path = Pathname.pwd.join("#{f.name}.rb")
+      path.write file_contents_at_revision(rev)
+
+      begin
+        old_const = Formulary.unload_formula(f.name)
+        nostdout { yield Formula.factory(path.to_s) }
+      rescue *IGNORED_EXCEPTIONS => e
+        # We rescue these so that we can skip bad versions and
+        # continue walking the history
+        ohai "#{e} in #{f.name} at revision #{rev}", e.backtrace if ARGV.debug?
+      rescue FormulaUnavailableError
+        # Suppress this error
+      ensure
+        Formulary.restore_formula(f.name, old_const)
+      end
+    end
+  end
+
+  def bottle_version_map(branch="HEAD")
+    map = Hash.new { |h, k| h[k] = [] }
+    rev_list(branch) do |rev|
+      formula_at_revision(rev) do |f|
+        bottle = f.stable.bottle_specification
+        unless bottle.checksums.empty?
+          map[f.pkg_version] << bottle.revision
+        end
+      end
+    end
+    map
+  end
+end